Machine for grinding facets on glasses for spectacles.



M. JUNGNICKEL.

MACHINE FOR GRINDING FAOETS 0N GLASSES FOR SPEGTACLES.

(Application filed Sept. 25, 1899.)

(No Model.)

Patented Aug. 27, I90l.

2 Sheets-Sheet l.

Ill

No. 68!,396. Patented Au 27, mm. m. JUNGNICKEL. MACHINE FOR GRINDINGFACETS 0N GLASSES FOR SPEGTAGLES.

(Application filed Sept. 25, 1899.)

2 Sheets-Sheet 2 (No Model.)

,THE NORms PEYERS co. Pumu umo wnumcmx. o. c.

UNITED STATES PATENT OFFrcE.

MAX JUNGNICKEL, OF RATHENOW, GERMANY.

MACHINE FOR GRINDING FACETS 0N GLASSES FOR SPECTACLES.

SPECIFICATION forming part of Letters Patent No. 681,396, dated August27, 1901.

Application filed September 25, 1899. Serial No. 731,652. (No model.)

To all whom it may concern:

, Be it known that 1, MAX J UNGNICKEL, optician, a subject of the GermanEmperor, residing at Rathenow, in the Kingdom of Prussia, German Empire,have invented a certain new and useful Machine for Grinding Facets onGlasses for Spectacles and the Like, of which the following is aspecification.

This invention relates to machines adapted for grinding facets onglasses for optical purposes, spectacles, and the like, and is intendedto obviate the difficulties presented by the machines heretofore in usefor that purpose, in'which it was either necessary to remove the glassfrom its support after the grinding of one side of the facet and thenadjust it again for the grinding of the other side, which gave rise tofrequent and very annoying irregularities in the configuration of thefacets, or which could only attain this purpose by the use of twogrinding-stones, the edges of which were set at an angle correspondingto the angle of the beveled edge it was desired to obtain. Furthermore,the grinding-machines in use heretofore for optical glasses were merelyintended to set the edge of the glass, so that it was always only withgreat difliculty that facets on the body of the glass itself could be.obtained by such machines with even an approximation of accuracy.

By the invention forming the subject of this application facets may beground upon such glasses by the employment of one grindstone only andwithout the necessity of removing the glass for the grinding of theother side of the facet, thus securing perfect sym* metry of both sidesof the facet.

The machine is especially distinguished by the use of a frame havingsuitable clamps for the attachment of the glasses to be worked and whichreceives an oscillating movement in accordance with the oval form of theglasses, the distance of the frame from the grinding-stone beingadjusted by means of a carriage and suitable gearing, while it isfurther capable of adjustment in adirection inclined toward the positionof the grindstone by means of a rotatable frame, so as to allow ofsubjecting first one and then the other side of the facet to thegrinding action.

My invention is illustrated in the accompanying drawings, whichrepresenta machine embodying my invention.

Figure l is a vertical longitudinal section of the machine. Fig. 2 is afront view of the machine. Fig. 3 is a longitudinal section of the framefor fastening the glasses. Fig. 4 is a cross-section of the said frame.Fig. 5 is plan view illustrating the different positions of thefastening-frame with relation to the grindstone. Fig. 6 is a detail ofthe arrangement for reciprocating the grindstone.

a is the glass to be operated upon and which is fastened between thejaws of the clamp 19 b, said jaws being attached to the shafts B B, andwhich are placed so as to be forming one straight line with theirrespective axes.

R R are springs which serve to tightly press the two jaws against eachother.

S is a hand-lever, by means of which the shaft B may be separated fromthe shaft 13 against the tension of its spring R in order to remove theglass or exchange it against another. The shafts are journaled in theframe 0, which is pivoted at O to the frame H, so as to be able toreciprocate in accord ance with the oval shape of the glass, the frame Hbeing made to turn upon a horizontal plate J.

F is the driving-shaft, journaled upon the frame -H and receiving itsmotion from the pulley G and to which gear-wheels E E are keyed,engaging with the toothed wheels D D upon the shafts B B.

Oval-shaped disks R, of steel or other suitable material, are attachedto the shafts B B adjacent to the plates T, of steel or other suitablematerial, fastened to the frame H. Springs V, having steel plates U,serve to press the disks R against the frame H. Upon rotating the shaftF this arrangement causes a rocking motion of the frame 0 with itsshafts B 13, thereby also rocking the glass at, fastened between thejaws b b, in accordance with the configuration of the disks R. Upon nowturning frame H, as represented in Fig. 5, upon the table J, to whichitis pivoted, as shown in Fig. 4 of the drawings, so as to assume aninclined position with relation to the grinding-stone Q, and upon nowadvancing the carriage K, upon which the table J is fastened, in thedirection of the grindstone, one side of the facet will be groundexactly corresponding to the form of the disks B. When the grinding ofone side of the facet has been finished, the frame II is turned so as toform an angle in the reverse direction and the other side of the facetground as usually.

A spring H is fastened to the frame H, a pin H being further providedand fitting into corresponding openings of the sector J, fastened to theedge of the table J, so asto allow of an exact adjustment of the frameII in its respective positions.

The forward movement of the carriage K, bearing the frame II, iseffected by means of a screw L, rotating in the guideway O and hearingat its end the worm-wheel M, which engages with the endless screw y,moved by the shaft X by means of strings, pulleys, or other suitablegearing. The forward movement of the carriage K is limited by theadjustable stop N. In the arrangement represented in the drawings theguideway O is also adjustable in a transverse direction by means of thescrew \V, fixed upon the transverse carriage P, so as to be able to alsoadjust the glass in a transverse direction with relation to thegrindstone.

Motion is imparted to the driving-shaft F from the pulley G, rotated byastring or belt from the shaft 1 which in its turn receives its motionfrom the main driving-shaft Shaft 11 imparts motion to the shaft 10,

which by means of a screw and worm-wheel rotates shaft X. The upper endof said shaft X is provided with an adjustable cam-disk Z, Fig. 6, whichact-uates the two disks Z of the shaft of the grindstone, and therebyslowly reciprocates the grindstone.

Instead of pivoting the frame 0 to the frame H at their lower ends itwill be found convenient for some purposes to use the drivingshaft F asa pivot for the frame 0, nothing being changed as regards the engagementof the gear-wheels E D E D.

The mode of operation of the machine is as follows: The optical glassbeing securely fastened between the jaws b h, flat spring 11 is slightlyraised and frame H is then shifted upon its turn-table until the pin Hexactly registers with the desired point of the scale attached to thesector J say thirty degrees. The spring I'I being then released, itstension will be sufficient to securely hold the frame II during theprocess of grinding. When the grinding of one side of the facet isfinished, the glass is shifted in the same manner to the oppositedirection without difficulty. If desired, it is obvious that a similarscale can be provided at the opposite end of the turn-table J, which ofcourse also necessitates the attachment of a second flat spring 11 atthe opposite end of the frame H.

What I claim, and desire to secure by Letters Patent of the UnitedStates, is-

In a machine for grinding facets to optical glasses the combination witha traveling carriage and a rocking frame and'former mounted thereon of avertically-rotatable frame for the support of the rocking frame, a scaleon the traveling carriage whereby the rotatable frame may be set at anydesired angle to the grindstone substantially as described.

In witness whereof I have hereunto set my hand in the presence of twowitnesses.

' MAX JUNGNIOKEL.

Witnesses:

HENRY HASPER, WOLDEMAP. HAUPT.

